Wellbore Stability Analysis of Sanish Field using 3-D Finite Element Model: Bakken Case Stud

Rock fracture mechanics theories have been used for more than 50 years in the oil and gas industry. Fracture mechanics is about understanding what will happen to the rocks in the subsurface when subjected to fracture stress. Much of what is used in hydraulic fracturing theory and design was developed by other engineering disciplines many years ago. However, rock formations often cannot be treated as isotropic and homogeneous. These assumptions affect the calculation of in-situ stresses which are important for designing hydraulic fracture and knowing the stability of wellbore. A Geomechanical model is built to investigate these problems and to predict the alterations and changes of the Geomechanical properties of the reservoir.;After the reservoir characterization and determination of the magnitude and direction of in--situ stresses, our next step is to prepare a 3-D Geomechanical model in ANSYS Workbench. Elastic anisotropy of the formation is included in the 3-D numerical models. The model will represent the Bakken Formation, having all its properties. After preparing a mesh for this model to carry out further studies, we apply stresses to the model so that it represents the depth at which the Bakken Formation is encountered while keeping the drilling conditions in mind. We analyze wellbore stability and predict wellbore behavior under stress alteration caused by drilling.